Field of the Invention
This application relates to a cable. In particular, this application relates to a cable with an insulated wire that is covered by a conductive coating, partially covered by a sparse shield, and covered by an insulating jacket.
Introduction to the Invention
Many medical devices include a base unit and a remote unit where the remote unit communicates information to and from the base unit. The base unit then processes information communicated from the remote unit and provides diagnostic information, reports, and the like. In some arrangements, a cable that includes a group of electrical wires couples the remote unit to the base unit. The size of the cable typically depends on the number of conductors running through the cable and the gauge or thickness of the conductors. The number of conductors running within the cable tends to be selected according to the amount of information communicated from the remote unit to the base unit. That is, the higher the amount of information, the greater the number of conductors.
In more advanced medical devices that use the base/remote unit arrangement, a great deal of information may be communicated between the remote component and the base unit. For example, a transducer of an ultrasound machine may communicate analog information over hundreds of conductors to an ultrasound image processor. Electrical cross-talk between adjacent conductors can become an issue. One way to reduce cross-talk is to increase the thickness of the insulating material that surrounds respective conductors. In some cases, a braided shield wire may be wrapped entirely around the insulating material to further improve the cross-talk characteristics. However, increased thickness of the insulating material and the addition of a braided shield wire result in a decrease in the number of conductors that may pass through a cable of a given diameter. To alleviate this problem, higher gauge conductors (i.e., thinner conductors) may be utilized. However, the thinner conductors tend to be more fragile, thus limiting the useful life of the cable. In addition, the cable attenuation is increased when the higher gauge conductors are used.